Okay, we are given 3406 and 2148. Let's add them up step by step.

Step 1: We'll start by adding the digits 6 & 8 in column 1 and get 14.
We'll write down the last digit 4 and carry the 1 to the next column.

Step 2: We'll start by adding the digits 0 & 4 in column 2 and get 5.

Step 3: We'll start by adding the digits 4 & 1 in column 3 and get 5.

Step 4: We'll start by adding the digits 3 & 2 in column 4 and get 5.

So, 3406 + 2148 = 5554.

